Means for separating magnetizable material



Oct. 28, 1958 M. BAERMANN MEANS FOR SEPARATING MAGNETIZABLE MATERIAL Filed July 17, 1951 3 Sheets-Sheet 1 INVE NTDR: Ncuc Baa/mam ATTORNESS' Oct. 28, 1958 M. BAERMANN MEANS FOR SEPARATING MAGNETIZABLE MATERIAL Filed July 17, 195i 3 Sheets-Sheet 2 I N VENTO m Max Baermann ATTORNEBS Oct. 28, 1958 M. BAERMANN 2,858,021

MEANS FOR SEPARATING MAGNETIZABLE MATERIAL Filed Juiy 17, 1951 3 Sheets-Sheet 3 INVENTOR MA X BAERMAN ATITORNEYS United States Patent MEANS FOR SEPARATING MAGNETIZABLE MATERIAL Max Baermann, Be'nsberg-Wulfshof, Germany, assignor to Robert Bauer, Basel, Switzerland Application July 17, 1951, Serial No. 237,168 Claims priority, application Germany July 27, 1950 12 Claims. (Cl. 209-215) This invention relates to a method and means for the transportation and/or separation of magnetizable material or objects containing the same, such as ironparts, iron ores, from powdery, liquid, or gaseous media.

The use of permanent magnets for holding or gripping objects made of ferromagnetic material is well known. It has also been proposed to transport objects from one place to another by magnets. Furthermore, the use of drums constructed of magnets is known for the separation of ferromagnetic particles out of liquids, for example, in the purification of oil. In addition, magnetic drums equipped with permanent magnets are already in use for the separation of materials such as-iron ores having ferromagnetic constituents. In all the well known fields of application, the magnetizable. particles adhere tightly to the magnetic system which must be moved mechanically toettect a change in position of the magnetizable particles. Furthermore, this method of operation necessitates that the transportation be carried out in According to the invention, a completely different method is used in order to transport magnetic materials or objects containing the same, or to sort or separate, magentizable materials out of powdery, liquid, or gase ous media. The new process consists in setting up a migrating magnetic field which varies continuously or in steps, approximately sinusoidally on the adhering surfaces of the'rnagnetic system which is rnultipoled by means of a continuous or step-wise position variation, for example, rotation of permanent magnets with respect to the pole pieces and the change in flux in 'themagnetic circuit caused by this. Thus, in contrast to all known methods, the movement of the ferromagnetic materialis no longer effected by the movement of the magnetic system itself but by changing the field strength of neighboring poles of the system so that a maximum of the field strength passes along the surface of the magnetic system which for practical purposes is composed of many pole pieces and takes along the magnetic material. Thus, in this type of transportation or sorting only the permanent magnet of the system is moved. The movement of the permanent magnet consists of rotation by means of which the magent can be broughtinto varyingly active positions in respect to the pole pieces and by means of which the field strength increases and decreases. However, the continuous or step-wise variation of the field strength for transportation can also be produced by displacing the magnets.

The advantages of the process are based on the fact that a magnetic transportation or separation can be car- 2,858,021 Patented Oct. 28, 1958 ice 2 ried out continuously in such cases in which the use of known devices would cause difiiculty. Of course, the possibility of a continuous transportation and separation also requires a continuous removal of the separated magnetizable material out of the powdery, liquid, or gaseous media.

In subject process, a constant polarity can be used in such a way that a north pole always becomes active as the operating pole or a south pole. However, according to the invention, a wandering magnetic field alternating in polarity can be produced.

An advantageous arrangement for carrying out the process according to the invention consists in that rings or discs provided with pole pieces and made of magnetic material are placed in layers on top of one an other alternatingly with rings or discs made of. nonmagnetic material to form a cylindrical, prismatic or other hollow body which encloses a roller-shaped permanent magnet magnetized transversely to the axis. The roller-shaped magnet is mounted so that it can rotate in such a way that each two rings which are separated by a layer of non-magnetic material together with their pole pieces displaced by divided by the number of pole pairs form pole piece pairs, the magentic axes of which are displaced relative to each other by a definite angle in the same direction of rotation. By such displacement -the pole piece pairs, varying strong magnetic fields are created upon rotating the roller-shaped magnet between neighboring pole piece pairs. The fields vary substantially according to a sine curve in respect to intensity and polarity and which progresses with the rotation of the magnet along the adhering surface of the magnetic system in one direction and carry along the magnetic material.

Rather than combining each two magnetizable rings provided with pole pieces into one pole piece pair, the invention can also be carried out by rings of magnetic material provided with pole pieces which are alternately stacked with rings of non-magnetic material to form a cylindrical or prismatic hollow body surrounding a rotatably mounted, roller-shaped permanent magnet which is magnetized transversely to the axis in such a way that the pole pieces of neighboring rings are always displaced with respect to one another in the same direction of rotation by one angle. In this arrangement, the field strength varies with the rotation of the magnet from one pole piece to the other so that a wave-like increase and decrease in the field strength is set up.

However, the device can also be constructed magnetically in such a way that the pole pieces of the rings made of a magnetically soft material and displaced singly or in pairs by 180 divided by the number of poles are placed in a straight line above one another and stacked together with non-magnetic intermediate pieces to form a cylindrical or prismatic hollow body in the hollow of which a permanent magnet magnetized transversely to the axis is mounted for rotation, the active pole surfaces of the permanent magnet being displaced in the same direction with respect to each other or formed into a spiral. By this means also a wandering magnetic field is attained on the surface of the body since the pole surface of the permanent magnet to be rotated forms a spiral and the pole pieces of the magnetically soft rings are straight above each other in the direction of the axis.

Rather than producing the varying magnetic field on the outside surface of the hollow body, the wandering field can also be produced on the inside surface by enclosing the rings, having the pole pieces of magnetically soft material on the outside, with a rotatably mounted ringshaped permanent magnet with strong poles and in which case the pole pieces of the magnetizable rings on the is varied in such a way that the pole pieces of the rings of magnetically .soft material, displaced singly or -in pairs by 180 divided by the number of the poles,"are placed in .a straight line above each other and stacked together with non-magnetic intermediate pieces into a cylindrical or prismatic hollow body. In such case,-theoutside surface enclosed by a rotatable, concentrically arranged permanent magnet, magnetized transversely to the axis and the active pole surfaces of which are displaced relative to each other in the same direction of rotation by one angle or run in a spiral shape.

The displacement of the pole pieces or the magnets with respect to each other is done by small angles of -l5. In this way, one complete circumference would be attained after 18 rings or pole pairs with a displacement of Thus, according to the magnitude of the displacement and the length of the magnetic system one or more circumferences or increases and decreases of the field strength result in one complete rotation of the magnet.

In the case of another practical arrangement for carrying out the process in which several magnetic systems with permanent magnets are arranged in series behind one another and can be switched into a short-circuit position from the operating position, and holding poles forming an adhering surface are used, the rotation of the separate permanent magnets, magnetized transversely to the axis, a magnetic field decreasing or increasing substantially uniformly from one pole to the other, appears with a change in position of the magnets relative to the poles of the adhering surface. A moving magnetic field, within whose maximum the magnetizable material is taken along corresponding to the Wandering speed of the field, can also be produced by the use of roller-shaped magnets which are always displaced by one angle in their phase of motion with respect to each other or run ahead or behind each other. The carrying along takes place not only by overcoming the forces of friction but also the force of gravity so that the ferromagnetic materials can be raised to a higher position as well as transported.

In the drawings:

Figure 1 is a top view of one transportation device having a two-pole magnet formed of a large number of stackedrings with non-magnetic intermediate pieces;

Figure 2 is a sectional view along aa of Figure 1 with the two-pole magnet removed;

Figure 3 is a top view of the adhering surface of the transportation device;

Figure 4 is a diagram of the magnitude of the attractive forces above the poles of the transportation device shown in Figure 3 at a definite point of time;

Figure 5 is a front view of the pole pair of a transportation device with a four-pole magnet;

Figure 6 is a perspective view of the transportation device with the magnet removed;

Figure 7 is a perspective view of a roller-shaped twopole permanent magnet body with spirally run pole surfaces;

Figure 8 is a top view of a transportation device having a ring-shaped permanent magnet;

Figure 9 is partly a side view of and partly a section through the device shown in Figure 8;

Figure 10 is a front view of a device having spiral poles;

Figure 1-1 is a section through the device shown in Figure 10.

The transportation device shown in Figures 1 and 2 is laminated out of soft iron rings 1 and the alternate intermediate non-magnetic rings 2 stapled to form a cylindrical body which is closed by covering pieces provided with bushings and not shown. The soft iron rings always have a pole piece 3 so that two such rings with pole pieces placed one on top of the other together with the two-pole rod-shaped permanent magnet 4, magnetized transversely to the axis and-mounted inside for rotation, form a magnetic circuit in which, for example, one of the rings is north magnetic and the neighboring ring which is separated from it by a non-magnetic disc 5 is south magnetic. The rings are displaced with their pole pieces over the entire length of the device always in the same direction of rotation by a definite angle so that upon rotating the magnet the next following rings in series always stand opposite the magnetic poles of the permanent magnet and in such position exhibit a maximum attractive force which progresses with the rotation of the permanent magnet along the pole surfaces or the adhering surfaces of the soft iron rings. This progression of the magnitude of the attractive force is approximately represented for the transportation device of Figure 3 by the sinusoidal curve 5 of Figure 4. In Figure 4 the different attractive forces of the poles at a definite position of the magnet are plotted as ordinates over the pole surface. Upon turning the magnet in the direction of the arrow (Fig. '3) the attractive forces are changed in sucha way that the maxima of the sine curve likewise progress in the direction of the arrow. Instead of making the permanent magnet two-poled, a four-pole magnet system (Fig. 5) can also be used advantageously in which case each ring 6 has two oppositely placed pole pieces 7 in front of which the four-pole permanent 8 is moved. By this arrangement, a greateruniformity in the course of the variation of the attractive forces is attained.

The distribution of the pole pieces 9, 10, 11, 12, and 13 in the interior of the pole body constructed of magnetic'and non-magnetic rings 14, 15 can be seen clearly in Figure 6. On the other hand, the pole attachments 16 (Figs. '8 and 9) could be placed on the outside of the magnetically soft or ferromagnetic rings 17 which are spaced by non-magnetic rings 18 and which are then surrounded by a ring or tube-shaped permanent magnet 19 with strong poles by whose rotation the moving field is produced in the interior.

A spiral form of the pole surfaces of a two-pole magnet can be seen in Figure 7. The spirally formed permanent magnet body, whether the poles are inside or outside, are used in the case of the devices in which the pole pieces of the soft iron rings are placed in a straight line parallel to the axis.

Figures 10 and 11 show a construction having ferromagnetic rings 21 which are spaced by non-magnetic rings 22 and are surrounded by a ring or tube-shaped permanent magnet 23. In this construction the magnet has spiral poles and is magnetized transversely to its longitudinal axis, the direction of the poles being indicated by spiral broken lines in Figure 11.

It will be understood that the method and means hereinbefore described are subject to many variations and modifications, all of which variations and. modifications are included within the folowing claims.

What is claimed is:

1. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, one of said bodies comprising conductingrings having pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the other body comprising at least one permanent magnet having a magnetic field which includes said pole pieces, said other body being rotatable in relation to the first-mentioned body, the location of opposed surfaces of the poles of said permanent magnet and said pole pieces being different from pole piece to pole piece.

2. A device for moving and sorting magnetizable maassaoai terial and media containing such magnetizable material, as Well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, the inner body comprising a roller-shaped permanent magnet magnetized transversely to its longitudinal axis, the inner body being rotatable relatively to the outer body, the outer body comprising ferromagnetic rings having inwardly projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces of two adjacent ferromagnetic rings being displaced in relation to each other by 180 divided by the number of pole pairs of the permanent magnet of said inner body, whereby the pole piece pairs thus formed are continuously displaced in relation to each other by one angle in the same direction of rotation.

3. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, the inner body comprising a spirally shaped permanent magnet magnetized transversely to its longitudinal axis, the inner body being rotatable relatively to the outer body, the outer body comprising ferromagnetic rings having inwardly projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces being displaced by 180 divided by the number of pole pairs of the permanent magnet of said inner body and being located in alinement with each other.

4. A device in accordance with claim 3, wherein the pole pieces are displaced individually by 180.

5. A device in accordance with claim 3, wherein the pole pieces are displaced in pairs by 180.

6. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, the inner body comprising ferromagnetic rings having outwardly projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces being displaced in relation to each other by one angle in the same direction of rotation, the outer body comprising a rotatably mounted round permanent magnet magnetized transversely to its longitudinal axis.

7. A device in accordance with claim 6, wherein the pole pieces are displaced individually by 180.

8. A device in accordance with claim 6, wherein the pole pieces are displaced in pairs by 180.

9. A device for moving and sorting magnetizable ma terial and media containing such magnetizable material, as Well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, the inner body comprising a roller-shaped permanent magnet magnetized transversely to its longitudinal axis, the inner body being rotatable relatively to the outer body, the outer body comprising ferromagnetic rings having inwardly projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces of adjacent ferromagnetic rings being displaced continuously by an angle in the same direction of rotation.

10. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, the inner body comprising ferromagnetic rings having outwardly projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces being located in alinement with each other, the outer body comprising a rotatably mounted round permanent magnet having spiral poles and magnetized transversely to its longitudinal axis.

11. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one within the other, one of said bodies comprising ferromagnetic rings having projecting pole pieces and non-magnetic rings of the same size located between said conducting rings, said rings being stapled to form an elongated hollow body, the pole pieces being displaced in relation to each other by such an angle that the sum of the displacement angles over the length of the body corresponds to at least one complete revolution, the other body comprising a rotatably mounted permanent magnet magnetized transversely to its longitudinal axis.

12. A device for moving and sorting magnetizable material and media containing such magnetizable material, as well as for separating magnetizable substances from said media, said device comprising two bodies located concentrically one Within the other, the inner body comprising a plurality of roller-shaped permanent magnets located next to each other in the axial direction and magnetized transversely to their axis, said magnet being interconnected so that their directions of magnetization are displaced at an angle in relation to each other, the outer body comprising ferromagnetic elements having inwardly projecting pole-pieces and non-magnetic spacers of the same size located between said ferromagnetic elements, said pole pieces being located in pairs in alinement with each other, whereby the permanent magnets may be turned from an operative position to a short-circuit position.

References Cited in the tile of this patent UNITED STATES PATENTS 572,370 Reed Dec. 1, 1896 686,835 Ruthenburg Nov. 19, 1901 1,214,817 Osgood Feb. 6, 1917 1,245,717 Henderson Nov. 6, 1917 1,948,419 Granigg Feb. 20, 1934 FOREIGN PATENTS 52,292 Germany Jan. 20, 1900 401,301 Great Britain Nov. 6, 1933 

